Department of Geology and Geophysics, University of Utah, 135 South 1460 East, Salt Lake City, UT 84112, USA.
J Chromatogr A. 2011 Jul 8;1218(27):4149-59. doi: 10.1016/j.chroma.2010.11.070. Epub 2010 Dec 4.
Various Be-containing micro-particle suspensions were equilibrated with simulated lung fluid (SLF) to examine their dissolution behavior as well as the potential generation of nanoparticles. The motivation for this study was to explore the relationship between dissolution/particle generation behaviors of Be-containing materials relevant to Be-ore processing, and their epidemiologically indicated inhalation toxicities. Limited data suggest that BeO is associated with higher rates of beryllium sensitization (BS) and chronic beryllium disease (CBD) relative to the other five relevant materials studied: bertrandite-containing ore, beryl-containing ore, frit (a processing intermediate), Be(OH)₂ (a processing intermediate), and silica (control). These materials were equilibrated with SLF at two pH values (4.5 and 7.2) to reflect inter- and intra-cellular environments in lung tissue. Concentrations of Be, Al, and Si in SLF increased linearly during the first 20 days of equilibration, and then rose slowly, or in some cases reached a maximum, and subsequently decreased. Relative to the other materials, BeO produced relatively low Be concentration in solution at pH 7.2; and relatively high Be concentration in solution at pH 4.5 during the first 20 days of equilibration. For both pH values, however, the Be concentration in SLF normalized to Be content of the material was lowest for BeO, demonstrating that BeO was distinct among the four other Be-containing materials in terms of its persistence as a source of Be to the SLF solution. Following 149 days of equilibration, the SLF solutions were fractionated using flow-field flow fractionation (FlFFF) with detection via ICP-MS. For all materials, nanoparticles (which were formed during equilibration) were dominantly distributed in the 10-100 nm size range. Notably, BeO produced the least nanoparticle-associated Be mass (other than silica) at both pH values. Furthermore, BeO produced the highest Be concentrations in the size range corresponding to < 3 kDa (determined via centrifugal ultrafiltration), indicating that in addition to persistence, the BeO produced the highest concentrations of truly dissolved (potentially ionic) Be relative to the other materials. Mass balance analysis showed reasonable sample recoveries during FFF fractionation (50-100%), whereas recoveries during ICP-MS (relative to acidified standards) were much lower (5-10%), likely due to inefficiencies in nebulizing and ionizing the nanoparticles.
各种含 Be 的微粒悬浮液与模拟肺液 (SLF) 达到平衡，以研究它们的溶解行为以及潜在纳米颗粒的生成。这项研究的动机是探索与 Be 矿石加工相关的含 Be 材料的溶解/颗粒生成行为与其在流行病学上表明的吸入毒性之间的关系。有限的数据表明，与研究的其他五种相关材料（含 bertrandite 的矿石、含绿柱石的矿石、 frit（一种加工中间体）、Be(OH)₂（一种加工中间体）和二氧化硅（对照）相比，BeO 与更高的 Be 致敏率（BS）和慢性 Be 病（CBD）相关。这些材料在两种 pH 值（4.5 和 7.2）下与 SLF 达到平衡，以反映肺组织中的细胞内和细胞间环境。在平衡的最初 20 天内，SLF 中 Be、Al 和 Si 的浓度呈线性增加，然后缓慢增加，或者在某些情况下达到最大值，随后减少。与其他材料相比，BeO 在 pH 7.2 时在溶液中产生相对较低的 Be 浓度；并且在平衡的最初 20 天内，在 pH 4.5 时在溶液中产生相对较高的 Be 浓度。然而，对于这两种 pH 值，BeO 在 SLF 中的浓度归一化到材料中的 Be 含量最低，这表明 BeO 在其他四种含 Be 材料中，在作为 SLF 溶液中 Be 的来源的持久性方面是不同的。在平衡 149 天后，通过使用电感耦合等离子体质谱法（ICP-MS）检测的流场流分离（FlFFF）对 SLF 溶液进行分级。对于所有材料，纳米颗粒（在平衡过程中形成）主要分布在 10-100nm 范围内。值得注意的是，BeO 在两种 pH 值下产生的纳米颗粒相关 Be 质量（除二氧化硅外）最少。此外，BeO 在对应于 <3 kDa 的大小范围内产生最高的 Be 浓度（通过离心超滤确定），这表明除了持久性之外，BeO 产生的真正溶解（潜在离子）的 Be 浓度最高，相对于其他材料。质量平衡分析表明在 FlFFF 分级过程中样品回收率合理（50-100%），而在 ICP-MS 中（相对于酸化标准品）回收率要低得多（5-10%），这可能是由于纳米颗粒的雾化和电离效率不高所致。
